Leo Cullen has warned Leinster not to fall into the Scarlets' turnover trap as the Blues chase down an historic double but prepare for a backlash at the Aviva Stadium today.

However the European champions are hugely boosted by the availability of Johnny Sexton, Dan Leavy and Isa Nacewa against the defending PRO14 title holders.

While Scarlets have moved their Munster-bound turnover specialist Tadhg Beirne to no 8 - in the absence of injured skipper John Barclay - Leinster are keeping back row enforcer Scott Fardy in reserve in what is a hugely experienced bench.

Leinster hammered the Welshmen in the Champions Cup semi-finals at the same venue only a few weeks ago, but were well beaten by the Scarlets this time last year in the PRO14 semis at the RDS.

“It’s making sure you’re not playing into their hands in the first place," said Cullen.

"We played into their hands if you wind back the clock to the semi-final last year.

"Watching that Glasgow semi-final (won by Scarlets) I thought, ‘Whoah, that looks like something that happened to us in the past’.

"It was a mirror image almost - the first three quick tries and 21 points.

"Trying to chase the game against that kind of defence is tough, and how do you try and go about doing that?